(1) Field of the Invention
The present invention relates generally to a locking window and, more particularly, to a window latch for such a window.
(2) Description of the Prior Art
Up to the end of World War II, most windows were constructed of wood. However, following the War, aluminum windows were initially constructed for low-end housing. Over time, the clear superiority of metal windows led to their use in many different types of housing. Similarly, vinyl windows were introduced in low-end housing in the beginning of the last decade. The use of vinyl windows has grown much more quickly than metal windows. In fact, the majority of windows are now constructed of vinyl.
During this time, locking windows have generally used metal latches similar to those that were initially used on wooden windows. Now, although vinyl windows are the predominant construction, there has still been a hesitancy to use plastic hardware. However, metal is much heavier than its corresponding plastic counterpart. Also, plastic retains its appearance when mishandled or otherwise misused which causes unacceptable chips to form on painted metal hardware. Also, in today's modern economy, window hardware may be made in another country. Accordingly, advantages of substantial weight savings and lower shipping costs have become even more important.
However, making a locking window having a plastic latch is more than a mere substitution of materials. Because plastic is generally more flexible than metal, attempts at constructing a window latch having a center mounted sweep latch have failed since there's not a sufficient amount of support across the center of the sweep to prevent bowing. The importance of bowing is primarily due to the requirement by most manufacturers that the sweep latch be able to maintain a static load of about 160 pounds. When a conventional center mounted sweep latch is formed from plastic materials, the bowing of the sweep latch is so substantial that the static load will actually slide off the latch arm. Because of this problem, such window latches have not been able to pass the static load test.
Thus, there remains a need for a new and improved locking window having a window latch which may be completely formed from chip resistant plastics while, at the same time, still provides sufficient strength due to its arrangement to resist normal wear and tear during assembly and use.